The present invention relates to a method of inspecting a negative film (referred to as a negative hereinafter) in a photographic processing apparatus.
It is known that a negative may be jammed and damaged during the advancing movement along a film passage in a photographic processing apparatus when it has a defect such as a slit adjacent to a perforation.
For preventing such an incident, the negatives are visually inspected one-by-one by an operator being loaded into the photographic processing apparatus. If any defective negative is found, it is reclaimed or repaired to ease the advancing movement along the apparatus film passage.
The visual inspection of the negatives is a troublesome task having very low efficiency, and misjudgment possible omission of a defect. If any defective film is loaded through possible omission of a defect, misjudgment, or fault action of a drive system in the film passage, it will be jammed and damaged causing cancellation of the printing process.
It is thus essential to stop the advancing movement immediately and remove the defective negative from the film passage by manual action of the operator upon jamming of the defective negative. This obligates the operator to pay constant attention to the advancing movement of the negative film to prevent generation of a troublesome situation. In addition, the inspection process for identifying any defect on the negative is not easy and requires a level of skill. It has been much desired to develop a technique for elimination of such a disadvantage.
It is an object of the present invention, in view of the foregoing, to provide a method of inspecting a negative for slits or cuts without visual checking of a service person or operator so that any defective negative film is exactly identified and prevented from loading into the film passage of a photographic processing apparatus.